1. Field of the Invention
The invention relates to an assembly for automatically rotating a vehicle rear view mirror. More specifically, the invention relates both to an assembly for automatically rotating a rear view mirror mounted on either side of a vehicle comprising a tractor hauling a semi-detached trailer, and to the rear view mirror itself.
2. Description of the Related Art
Trailered vehicles are well-known. Referring to FIG. 1a, a trailered vehicle 20 comprises a semi-detached trailer 22 mounted to a tractor 24. Trailer 22 is mounted at a hitching point 26, typically referred to as a "fifth wheel," positioned at a rear end 28 of the tractor's chassis 30. The tractor and trailer generally align to define an imaginary axis 32. A passenger-side rear view mirror 34 typically is mounted on a passenger-side door of the tractor, and positioned generally in alignment with the axis 32, so that the driver can see the passenger-side rear corner 36 of the trailer 22. The driver typically adjusts this passenger-side mirror 34 either electrically, or by hand, according to the length of the trailer 22. The driver's field of vision in the passenger-side mirror is depicted by reference numeral 38. The above-described relationship is shown in FIG. 1(a), depicting the right hand side as the passenger side, as is common for example in North America and continental Europe. Alternatively, a reversed relationship applies in other countries where the passenger side is on the left hand side.
A problem occurs when the driver enters a turn, either going forward or reversing. As the tractor turns, the trailer pivots with respect to the tractor, forming an angle therebetween. The passenger-side rear view mirror, however, remains stationary. The trailer 22 therefore blocks the field of vision 38, causing the driver to lose sight of the passenger-side rear corner 36 of the trailer, along with any object in the vicinity. This problem is depicted in FIG. 1(b). Tighter turns obviously exacerbate this problem.
The resultant loss of rear visibility creates potentially dangerous situations. Whether driving on winding roads, or attempting to back the trailer into a parking lot or a loading dock, the driver's inability to see other vehicles, persons, or other objects in his passenger-side mirror can result in property damage or more serious accidents.
Reports published in 1994 indicate that out of 330,000 reported truck crashes in the U.S. in 1991, 19.1% of these accidents involved backing, turning, lane-changing, or merging maneuvers by trailered vehicles. These crashes accounted for 1.0% of all fatalities, 10.8% of injuries, and 6.3% of costs for trailered vehicle accidents that year, with total direct monetary losses estimated at over $250 million.
A number of commercially available warning systems exist that give a driver a warning of objects behind his truck during a turn. Despite the desirability of such systems, surveys of professional truck drivers have noted several shortcomings with the available systems. For example, existing devices are not easy to install. Another problem exists with the reliability of the existing systems, including damage to the systems while in use. Another problem is the difficulty of using the existing systems. In short, existing systems to detect and warn drivers of objects behind a truck have limited areas of coverage, provide inconsistent warnings, and rarely are used.
A better solution is to enable the driver to rely on his passenger-side rear view mirror by providing the mirror with the capability to rotate in response to a vehicle turn. Past attempts to provide such a device have met with limited success, as evidenced by the fact that no such device is in widespread use in the trucking industry.
An automatically adjustable passenger-side rear view mirror assembly is desired for trailered vehicles that is easy to install and operate, and is reliable under normal truck-driving conditions and environments.
Additional objects and advantages of the invention will be set forth in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. The objects and advantages of the invention may be realized and obtained by means of the combinations described in the attached claims.